Spotting submarines



- 20, 1946. J. T. BEECHLYN SPOTTING SUBMARINES Filed May 22, 1943 IN VENTOR. JOHN -T. BE ECHLYN Patented Aug. 20, 1946 2,405,990 SPOTTING SUBMARINES John T. Beechlyn,

Submarine Signal Company, corporation of Maine Worcester, Mass., assignor to Boston, Mass, a

Application May 22, 1943, Serial N0. 488,320

The present invention relates to means and method of locating submerged objects and is more particularly applicable for military purposes in locating the position of enemy submarines. While the present sound ranging methods are usefully employed for this purpose and are able to locate a submarine and provide bearings and distance measurements so that they ma be tracked down, some uncertainty and confusion still exists when the searching vessel comes into the near vicinity of the submarine in a radius perhaps of 50 to 250 yards and over the area where the submarine is at the observing moment. In this range when the surface vessel is closing in on the submarine, skillful maneuvering of the submarine may make it difficult or even impossible to obtain bearings from the searching surface vessel. The surface vessel in this case must contend not only with a great maneuvering ability of the submarine under these conditions, but also with the fact that the submarine has a three dimensional maneuverability providing theoretically at least infinite possibilities of escape.

The applicant has devised a method and means whereby the depth and position of the submarine at this time of the search may be observed and followed. The means of the present invention avoid the necessity of using sound waves which is at times a distinct advantage especially when the submarines are in groups or when they are attacking a convoy or more than one vessel. Under these conditions, the water noises r noises from the various vessels in the vicinity may be very confusing and interfere with eflicient sound ranging as also may be the case after the water medium has been disturbed by the explosion of depth charges or other explosive attacking means. The invention will be more readily and fully understood from a consideration of the specification set forth below describing the invention when taken in connection with the drawing illustrating the same in which Fig. 1 shows an elevation partly in fragmentary section of a part of the invention. Fig. 2 shows a modification in fragmentary section of a portion of the device corresponding in the drawing to Fig. 1. Fig. 3 shows a section taken on the line 3-3 of Fig. 1. Fig. 4 hows in elevation a device by which the structure of Fig. 1 is fired. Fig. 5 shows a view as seen in the direction 5-5 of Fig. 4 and Fig. 6 illustrates schematically the method by which the missiles of Fig. 1

are directed in a pattern over a given water surface.

In the present invention a group of missiles of a special construction are projected from a 4 Claims. (01. 116-26) suitable device in such a manner that they shower down substantially simultaneously over a given chosen area. These missiles upon reaching the water substantially at the same time sink vertically at a constant rate until they come in contactwith a submerged object, or the bottom. When they strike a submerged object, the lower or weighted part of the missiles are released and what is left shoots rapidly vertically upward to the surface, popping out of the water for a considerable height. Various means may be used to make the missiles more noticeable when they break through the water surface. They may be painted with a bright color or provided with some special reflecting means, or they even may provide a loud explosion. The buoyancy of the missiles may be so adjusted that they sink at one rate and rise at the same or a different rate. any event, the rates of sinking and rising Will be known and from a measurement of the time interval between the missiles hitting the water and until they again reappear will give a measurement of the submerged object. In most cases, since the water depth will be known, there will be no confusion between those which come to the surface from the bottom, and those which come to the surface from a submerged object. In Fig. 1. the missile is generally indicated by I. This includes an evacuated air filled body 2 having generally a stream-lined shape so that the resistance of the body to the Water is low, and constant. The body 2 may be made of glass, thin metal, plastic, or other suitable material, which is not readily shatterable under the conditions under which the device is used. The body 2 may at its end be lightly loaded with a metallic cap, 4', having directive fins 4, 4, 4, 4 positioned at right angles to each other at the end of the body. .The body may also be provided with a tail projection 5, cylindrical in shape, with an annular recess 6 in which the latch member I normally rests. The latch member I is mounted in the weighted stream-lined body 8, which abuts the exterior side walls of the stream-lined body 2. This weighted body which has a stream-lined outer contour, is provided with a centrally symmetrically bore or hole 9 in which the projection 5 from the tail of the body 2 is positioned. The bore 9 extends 1ongit-udinally through the tail end In of the body 8 and in it is fitted for free motion a rod or shaft I I. The body 8 in the end portion I0 is also provided with a recessed portion l2 exposed or recessed as far as the shaft H. The latch 1 previously mentioned is formedas a part of a fiat pivoted member [3, pivoted in the body ID by if the missiles are means of the shaft M. This pivoted element I3 the wall 8 to permit the free entry of water as the two parts of the missile separate.

The missile described in Fig. 1 may be propelled from a projector 20 mounted on a deck 2| of a vessel. The missiles are'balanced to fall straight down in the water and upon the end of the pin II striking the submarine, the body 2 is released and travels straight up to the surface.

so that the position at which it reappears is vertically above the point at which it struck the submarine. A convenient method for this is indicated in Fig. 4 which shows a compressed air or gas supply 22 which feeds a cylindrical valve 23-. The cylindrical valve 23 has a rotor element 25 into which the compressed air from the supply source 22 is fed. The rotor 25 is provided with a longitudinal port 24 and when the handle 25 is turned rotating the rotor 25, the longitudinal port opens successively to groups of projector tubes 21, 28, 29, 3!]. As indicated in Fig. 4 a number of tubes are provided in the same plane as shown by 21,21, etc. The individual tubes in any one plane flare out at slightly different angles and each group is spaced in a fanned-out position with respect to the other groups whereby a given chosen area is covered over which the missiles will drop. By shooting or projectin each one of the missiles with the same Vertical velocity component, the missiles will reach the same vertical height h, as indicated in Fig. 6, and will fall at different points into the water all at substantially the same time. component of the missiles may be controlled by properly proportioning the end openings in the tubes or by any other suitable means for instance, fired by explosive charges, the size of the charges may be varied to produce the desired velocities so that their vertical components are. maintained constant. It naturally follows from the description just given that if the angle of direction of the missiles are all the same, then equal muzzle velocities will provide substantially the same kind of dropping to the water surface. It is of course noted that varia tions in wind velocity and direction may have an efiect upon these factors, but in general, this effect may be neglected since in general all missiles will go in the same direction and all fall in a rather confined area. The operator may time missiles either fromthe firing out of the projector or from the instant when they reach the water. If timing is done from the instant of projection of the missiles some mechanical arrangement may be used whereby th'erotation of the handle 26 will start the timing interval. The rising of the projector out of the Water again, however, after a submersible object has been encountered will in general be noted either by the eye or by some stop watch mechanism to end the timing interval when the missile is observed coming out of the water. The computation'of the depth is a simple proportioned rate. That is if one second represents feet of depth, two seconds would represent' lO feet and so on, so that if the time interval should be 10 seconds as observed, then the depth may-be judged a 200 The vertical velocity,

against which a' helical m simultaneously into the the time; intervals projectiles Strike water surface of suflicient intensity 'to illuminate the reflecting surfaces 32, 33,

34, so that they may be visible from the searching vessel when they have broken through the water after coming in contact with the submerged body or submarine. place of or in addition to the refle'cting surfaces 32, 33, 34, which may extend in a belt around the missile element an explosive device 35 may be used. This explosive device 35 may be formed as a portion of the nose of the missile 36 and may comprise a hood 31 provided with an internal annular shoulder 38 prin 39 bears. The hood may be cemented with a soluble cement to a collar 40 extending over the joint between the hood 31 and the body 3! of the missile 36. This collar 40 fits over the increasing stream-lined wallformed by the nose of the missile and the body portion of the missile itself and is at the same time cemented both to the .hood andto the body portion of the missile .by a soluble cement as mentioned so that after the device gets into the'water it will gradually be loosened after a time interval. The helical spring 39 bears against a partition 4| located between the nose and the rest of the body portion of the missile so that the head is tensioned awayfrom the rest of the body by the spring at all times. Centrally, under the spring is located an explosive element 43 which may be ignited by a cap member 44 suspended'between .the end 45 of the nose and a well 46 in the plate 42. While the missile in Fig. 2 is in the water either the cement has not been sufiiciently loosened or the pressure of the water on the shaft 40 is such so that the top nose 31 will remain inplace. When, however, the missile has shot out of the water, the spring 39 will force the nose away from the rest of thebody igniting the cap-43 and exploding a powder 44 causing a detonation and a visible light which maybe seen'within the range that the device is, used. In' this manner the device may have use both for day-light and night searching and attack'and may be used "as initially described in hunting and tracking down submarines.

Having now described my invention, I claim: 1'. A method of -spotting submerged submarines which compris$ firing a pearance of the projectiles when they break the surface and noting their distance and bearing.

' 2. A method of spotting submerged submarines with a projectile having a negative buoyancy before striking the submarine and a positive buoyancy thereafter, which comprises"firingi a group of projectiles directed to drop substantially water in a, given area known rates, measuring between the moment when the the water anu reappear again and descend and rise at 4. A system for spotting submerged submarines comprising in combination a projectile having a negative buoyancy before striking the submarine and means released from the projectile upon striking to provide a positive buoyancy, and means for firing groups of said projectiles adapted to space the projectiles over a given area and to drop substantially simultaneously into the Water, said means providing substantially the same ver- 10 tical velocity component for the projectiles.

JOHN T. BEECHLYN. 

